1 files changed, 121 insertions, 0 deletions
diff --git a/src/dolphin/MathUtil.h b/src/dolphin/MathUtil.h
new file mode 100644
index 0000000..b1dbbae
--- /dev/null
+++ b/src/dolphin/MathUtil.h
@@ -0,0 +1,121 @@
+// Copyright 2008 Dolphin Emulator Project
+// Licensed under GPLv2+
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <algorithm>
+#include <vector>
+
+#include "Compat.h"
+
+#include "../types.h"
+
+#ifdef _MSC_VER
+#include <intrin.h>
+#endif
+
+namespace MathUtil
+{
+constexpr double TAU = 6.2831853071795865;
+constexpr double PI = TAU / 2;
+
+template <typename T>
+constexpr auto Sign(const T& val) -> decltype((T{} < val) - (val < T{}))
+{
+  return (T{} < val) - (val < T{});
+}
+
+template <typename T, typename F>
+constexpr auto Lerp(const T& x, const T& y, const F& a) -> decltype(x + (y - x) * a)
+{
+  return x + (y - x) * a;
+}
+
+template <typename T>
+constexpr bool IsPow2(T imm)
+{
+  return imm > 0 && (imm & (imm - 1)) == 0;
+}
+
+constexpr u32 NextPowerOf2(u32 value)
+{
+  --value;
+  value |= value >> 1;
+  value |= value >> 2;
+  value |= value >> 4;
+  value |= value >> 8;
+  value |= value >> 16;
+  ++value;
+
+  return value;
+}
+
+template <class T>
+struct Rectangle
+{
+  T left{};
+  T top{};
+  T right{};
+  T bottom{};
+
+  constexpr Rectangle() = default;
+
+  constexpr Rectangle(T theLeft, T theTop, T theRight, T theBottom)
+      : left(theLeft), top(theTop), right(theRight), bottom(theBottom)
+  {
+  }
+
+  constexpr bool operator==(const Rectangle& r) const
+  {
+    return left == r.left && top == r.top && right == r.right && bottom == r.bottom;
+  }
+
+  T GetWidth() const { return abs(right - left); }
+  T GetHeight() const { return abs(bottom - top); }
+  // If the rectangle is in a coordinate system with a lower-left origin, use
+  // this Clamp.
+  void ClampLL(T x1, T y1, T x2, T y2)
+  {
+    left = std::clamp(left, x1, x2);
+    right = std::clamp(right, x1, x2);
+    top = std::clamp(top, y2, y1);
+    bottom = std::clamp(bottom, y2, y1);
+  }
+
+  // If the rectangle is in a coordinate system with an upper-left origin,
+  // use this Clamp.
+  void ClampUL(T x1, T y1, T x2, T y2)
+  {
+    left = std::clamp(left, x1, x2);
+    right = std::clamp(right, x1, x2);
+    top = std::clamp(top, y1, y2);
+    bottom = std::clamp(bottom, y1, y2);
+  }
+};
+
+}  // namespace MathUtil
+
+float MathFloatVectorSum(const std::vector<float>&);
+
+// Rounds down. 0 -> undefined
+inline int IntLog2(u64 val)
+{
+#if defined(__GNUC__)
+  return 63 - __builtin_clzll(val);
+
+#elif defined(_MSC_VER)
+  unsigned long result = ULONG_MAX;
+  _BitScanReverse64(&result, val);
+  return result;
+
+#else
+  int result = -1;
+  while (val != 0)
+  {
+    val >>= 1;
+    ++result;
+  }
+  return result;
+#endif
+}